"Work That" was released as the second single on December 18, 2007 and managed to peak inside the top 20 of the BillboardHot R&B/Hip-Hop Songs and number 65 in the Billboard Hot 100. The third official single "Stay Down" reached the top 40 R&B charts, and was chosen in favor of "Hurt Again", which was originally the third single, but eventually was only a radio single by receiving airplay in Spring 2008.
In an interview for Blues & Soul, Blige explained the significance of the album's title, stating:
I started writing the record right after that whole gigantic day I had at the Grammies last year. So it was important to me to get across to my fans that whole feeling I was going through of 'How do I sustain this breakthrough? How do I continue to remind myself I'm in a better place?'... And the only way to continue to stay in that place is to GROW! I believe the majority of people out there, if something uncomfortable is going on in their lives, are forced to either go back to where they were, or to GROW – and that that tension is called PAIN. So the light, happy songs on the album are celebrating my growth. While the less poppy, darker tracks represent the places I'm forced to grow out of. So in that way the title represents the growth, as well as the understanding that – in order for anything to develop – it has to have some kinda tension behind it.
"Just Fine" was released as the album's lead single on October 2, 2007. The single was the only single from the album which was released in multiple formats. The single peaked at #22 on the Billboard Hot 100 and #3 On the U.S. Billboard Hot R&B/Hip-Hop Songs chart. In the UK, the song performed well peaking at #16 on the official chart. "Work That" was released as the album's second single on December 18, 2007. The single charted from digital downloads when the album was released, and eventually peaked at #65 on the Billboard Hot 100 but did become a top 20 hit on the Billboard Hot R&B/Hip-Hop Songs. The song "Hurt Again" was supposed to be released as the official third single released from Growing Pains, but at the last minute was changed in the favor of "Stay Down". Between the loss of momentum from the album's first and second single and lack of promotion for the single, "Stay Down" did not chart on the Billboard Hot 100 chart; it peaked at #34 on the Billboard Hot R&B/Hip-Hop Singles chart.
Growing Pains sold 629,000 copies in its first week and debuted at number two on the U.S. Billboard 200 chart and number one on the R&B chart. In its second week the album climbed to number one on the Billboard 200 with 204,000 copies sold. In the UK, the album entered the charts at Number 6, making it her highest charting album there since No More Drama in 2001 with first week sales of 21,755. In Germany, the album was her worst one charting, peaking #48 and staying on the German Albums Chart for only 3 weeks. As of 27 March 2010, the album had sold 81,681 copies in the UK.
Growing Pains received positive reviews from most music critics. At Metacritic, which assigns a normalized rating out of 100 to reviews from mainstream critics, the album received an average score of 77, based on 17 reviews, which indicates "generally favorable reviews".Allmusic editor Marisa Brown gave it four out of five stars and called it "a mature, polished, and utterly professional set of well-crafted songs", noting that "the album takes an even greater step toward pop". Alex Macpherson of The Guardian complimented its themes of Blige's "past and present", while citing the track "Roses" as "one of the best songs of her career".NME commented that it "finds Blige on chirpier form". Michael Arceneaux of PopMatters complimented Blige's "cheerful demeanor" on the album and called it "a good addition to the Mary J. Blige catalogue".USA Today's Edna Gundersen wrote that "Her vulnerability and vocal prowess are undeniable, and resistance melts away as her voice [...] commands and communicates with startling clarity". Steven Hyden of The A.V. Club commended Blige for "reaching beyond the relative stability of her personal life and playing up the vulnerable everywoman persona that's long resonated with her female fanbase".BBC Online's Talia Kraines commended Blige for "keeping it real" and complimented her "empowering emotion".
However, Andy Gill of The Independent commented that "it's hard to tell whether the whiplash snares and crisp handclap grooves [...] are suited to [Blige's] needs here" and criticized "Blige's capitulation to R&B cliché, with all women downtrodden and all men culpable, and a corrosively bling-driven worldview".Slant Magazine's Eric Henderson called the album an "overstuffed collection of affirmations, self-definitions, and keepin'-it-real-isms" and wrote that "what's both most compelling and most limiting about Blige's Growing Pains: She keeps her most salable characteristic, her emotiveness, under duress, which provides tension but no release". Alfred Soto of The Village Voice noted "no more drama, but plenty of (occasionally excellent) melodrama", adding that "as her acting chops diminish, her command over plush, slightly jagged contempo r&b improves". Writing for Rolling Stone, critic Robert Christgau commented that "the tone of her confessions has changed with her music", stating "Growing Pains is an edgier record than The Breakthrough, but Blige has definitely lost or just outgrown the brassy urgency of her twenties". In his consumer guide for MSN Music, Christgau described the album as "an expensive, honorable, credible sampler of the hottest current R&B brands", and gave it an A- rating, indicating "the kind of garden-variety good record that is the great luxury of musical micromarketing and overproduction".